HIGH RESOLUTION ELECTROMECHANICAL MAPPING OF THE HEART We have developed the hardware, MR pulse sequences and data analysis software to perform high resolution mechanical function maps while simultaneously recording electrical activation maps from an electrode "sock" surrounding the heart. The electrical recording system has been made MR compatible so that the MR image quality is not degraded by the presence of the sock around the heart. Coupled electromechanical activation maps are being generated by registration of the electrical maps with the mechanical maps generated from MRI tagging studies. The effect of ischemia on the electromechanical can now be studied in detail, perhaps leading to the ability to precisely distinguish viable from non-viable tissue.